Malaria is a prevalent infectious mosquito- borne disease. The distribution of malaria occurs as a broad belt around the equator with high prevalence in countries with hot climates. In a significant new discovery, US scientists have successfully genetically modified and bred a mosquito that is resistant to malaria infection, essentially rendering them impotent as vectors, or distributors, of the disease-causing parasite.
Malaria is caused when the female Anopheles mosquito is infected by the malaria parasite which resides in their salivary glands. The parasite is then introduced to humans and spread when these infected mosquitoes bite and feed. US scientists have discovered a technique that could help to halt the spread of malaria.
The new technique involves introducing a “resistant” gene into the mosquitos DNA using a special, emerging molecular biology/gene editing technique known as Crispr. This DNA insert helps to tackle the invading parasite by coding for antibodies that combat the parasite. The result of this is a mosquito host that is resistant to malaria parasite, and hence cannot further transmit it. Importantly, breeding of these genetically edited results in resistant offspring.
Prof David Conway, from the London School of Hygiene & Tropical Medicine, stated: “It’s not the finished product yet but it certainly looks promising. It does look like the genetic editing works”. It is conceded that this would not be the sole or “Holy Grail” solution to the malaria problem. A vast amount of research is focusing on new ways to reduce malaria spread, and this is not the first instance of GM mosquitoes being exploited.
In 2014, it was reported that scientists had discovered a way of using GM mosquitoes that produce 95% male offspring. The approach tackles the problem on two fronts, reducing the number of disease transmitting females, and causing an overall population crash. Other research investigates genetically modifying mosquitoes to become infertile to reduce or eliminate the population.
With some warning about the repercussions of eliminating the mosquito population, this is an exciting development in the fight against malaria, which offers an alternative method of disease control.